Air-tight lid



- Patented .Ian. 3, "299..

No. mm

F. w.' ron'srsn. AIR TIGHT uu'.

(Applipitinn filed m. 11, 1898.)

(Ho Modal.)

INVENTOR Jib); if fizz/z %%7 WITNESSES 4. 04 a??? UNITED STATES PATENT Fries.

FREDERICK V. FORSTER, OF PHILADELPHIA, PENNSYLVANIA.

AIR-TIGHT LID.

SPECIFICATION forming part of Letters Patent No. 616,910, dated January 3, 1899.

Application fil dMarch 11, 1898. Serial No. 673,446. iNO model.)

To all whom it may concern.-

Be itknown-thatl, FREDERIoKWFoRsrER, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Air- Tight Lids; and I do declare the following to be a full, clear, and eXact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

My invention relates to an improvement in air-tight lids which may be applied to boxes, barrel-heads, hand-holes for clean-outs of waste-pipes, and other devices where air-tight lids are required. I attain this object by the construction illustrated in the accompanying drawings, in which Figure 1 is an inverted. view of the closed lid complete; Fig. 2, a section of the sameon line A A, and Figs. 3 and 4. isometrical views of the cross-shaped braces.

Similar letters refer to similar parts through out the several views.

B B represent a metal plate or cover for the reception of the lid. This plate or cover may be the head of a barrel, the top of a box, the upper flange of a hand-hole for a cleanout, as indicated by the section Fig. 5, or a part of any other device which requires an air-tight lid. This plate or cover is provided with a circular rim P P around the hole for Ehe lid. This rim is turned out on the inner ace.

H H is the circular metal lid proper. The same has aproj ecting rim Q Q, which is turned off on the outer face to correspond to the turning out of the inner face of the rim P P, leaving a spaceLbetween the two rims for a gasket, which may be of rubber, lead, leather, paper, or some other suitable material. This gasket is not shown here. A small groove M M is turned into the lid to allow the gasket to hold by its own elasticity if of rubber or to be tied in if of other material to prevent the same falling off when the lidis being removed.

E E F F and O O D D are the cross-shaped braces, the arms E F O D of which are considerably shorter-4o wit, about one-third to one-fourth of the length-than the other arms 0 D F, while the arm E is longer, as will be explained below. The ends E F C D of these braces are turned up, the ends E and F being higher than C and D. The cross-shaped brace E E F F has a circular reinforcement R in the center, into which is firmly secured the head 0 of the bolt 0 O. N is a washer, and G a thumb-nut. The end 0 of the bolt 0 O is upset, so as not to allow the thumb-nut G to be removed.

' The way of applying the lid is the following: Turn the thumb-nut G to the left until it grips tight at the upset end 0 of the bolt 0 0. Continuing to turn the thumb-nut G in the same direction it will turn the cross-shaped brace E E FF in the same direction until it reaches the position E E F F-, (shown in dotted lines in Fig. 1,) the arm F being long enough to clear the arm 0, and the upturned ends F I and E being high enough to clear the arms 0 and D. The arm E being of the same length as the arm 0, its upturned end will strike the upturned end of 0 when it reaches the position E. The brace O C D D being held in place by the pin I, which may be either fastened to the lid or made in one piece with the same, the brace E E F F cannot go farther than to the position E E F F. With this position of the cross-shaped braces the lid can easily be inserted in the plate or cover B. When the lid is in place, with the gasket in the space L, turn the thumb-nut to the right. As it has gripped the upset end 0 of the bolt 0 0, it will turn the cross-shaped braceE E F. F in the same direction, movingit from the position E E F F until the arm E E strikes the pin K, which may also be fastened to the lid or made in one piece with the same and prevent the brace E E F F going any farther. Turning the thumb-nut G farther to the right it will disengage itself from the grip on the upset end of the bolt and tighten the same, pressing the arms 0 D E F against the bottom of the rim of the plate or cover, the arms 0 and D against the under side of the lid, and the arms E and F against the arms 0 O and D D of the brace O G D D. By sufficiently tightening the thumb-nut G the turned-0E faces of the rims of the lid H H and the plate or cover B B will press against the gasket in the spaceL, the arms of the F being higher than C and D, and the arm F F being so much longer at the end F as to clear the arm 0 when turned, as explained above. 0' shows the holes for'the bolt 0 0, while 0" shows the seat for the head 0 of this bolt. 1' is the hole for the pin I.

The plate or cover 13 B, the lid H II, and all other parts appertaining to the device specified above may be made of cast-iron, brass, bronze, or any other metal or alloy suitable to the purposes it should be required for.

I am aware that prior to my invention airtight lids for the purposes mentioned and of similar construction have been made and in use, and I do not claim anything that was known or applied in or for the same heretofore; but

What I do claim as my invention, and desire to secure by Letters Patent, is-- 1. In the construction of an air-tight lid,

the combination of a plate or coverB B with a projecting rim P P, the lid proper II II with the pins I and K and a projecting rim Q Q, with aspace L L between the faces of the rims and a gasket in this space, two cross-shaped braces, C G D D and E E F F, a bolt 0 O securely fastened to one of the cross-shaped braces, a washer N and a thumb-nut G all substantially as set forth and described.

2. In the construction of an air-tight lid the combination of the lid proper with a pair of cross-shaped braces, the arms of which form lovers with unequal arms, the longer arms to have upturned ends, the four short arms of equal length among each other, three of the longer arms of the two braces of equal length among each other and the one long arm of one brace longer than the three other long arms, with a bolt 0 O with upset end 0, a washer N and thumb-nut G, all substantially as set forth and described.

In testimony whereof I affix my signature in presence of two witnesses.

FREDERICK \V. FORSTER. lVitnesses:

M. G. SCHAEFER, A. \V. SPROA'I. 

